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1.
BMC Biol ; 21(1): 208, 2023 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-37798721

RESUMEN

BACKGROUND: Domestication and introduction of dairy animals facilitated the permanent human occupation of the Tibetan Plateau. Yet the history of dairy pastoralism in the Tibetan Plateau remains poorly understood. Little is known how Tibetans adapted to milk and dairy products. RESULTS: We integrated archeological evidence and genetic analysis to show the picture that the dairy ruminants, together with dogs, were introduced from West Eurasia into the Tibetan Plateau since ~ 3600 years ago. The genetic admixture between the exotic and indigenous dogs enriched the candidate lactase persistence (LP) allele 10974A > G of West Eurasian origin in Tibetan dogs. In vitro experiments demonstrate that - 13838G > A functions as a LP allele in Tibetans. Unlike multiple LP alleles presenting selective signatures in West Eurasians and South Asians, the de novo origin of Tibetan-specific LP allele - 13838G > A with low frequency (~ 6-7%) and absence of selection corresponds - 13910C > T in pastoralists across eastern Eurasia steppe. CONCLUSIONS: Results depict a novel scenario of genetic and cultural adaptations to diet and expand current understanding of the establishment of dairy pastoralism in the Tibetan Plateau.


Asunto(s)
Crianza de Animales Domésticos , Pueblo Asiatico , Dieta , Leche , Animales , Perros/genética , Humanos , Tibet , Rumiantes
2.
Ann Hum Biol ; 51(1): 2310724, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38594936

RESUMEN

BACKGROUND: Pastoralists live in challenging environments, which may be accompanied by unique activity, energy, and water requirements. AIM: Few studies have examined whether the demands of pastoralism contribute to differences in total energy expenditure (TEE) and water turnover (WT) compared to other lifestyles. SUBJECTS AND METHODS: Accelerometer-derived physical activity, doubly labelled water-derived TEE and WT, and anthropometric data were collected for 34 semi-nomadic Daasanach adults from three northern Kenyan communities with different levels of pastoralist activity. Daasanach TEEs and WTs were compared to those of other small-scale and industrialised populations. RESULTS: When modelled as a function of fat-free-mass, fat-mass, age, and sex, TEE did not differ between Daasanach communities. Daasanach TEE (1564-4172 kcal/day) was not significantly correlated with activity and 91% of TEEs were within the range expected for individuals from comparison populations. Mean WT did not differ between Daasanach communities; Daasanach absolute (7.54 litres/day men; 7.46 litres/day women), mass-adjusted, and TEE-adjusted WT was higher than most populations worldwide. CONCLUSIONS: The similar mass-adjusted TEE of Daasanach and industrialised populations supports the hypothesis that habitual TEE is constrained, with physically demanding lifestyles necessitating trade-offs in energy allocation. Elevated WT in the absence of elevated TEE likely reflects a demanding active lifestyle in a hot, arid climate.


Asunto(s)
Metabolismo Energético , Agua , Adulto , Masculino , Humanos , Femenino , Kenia , Ejercicio Físico , Antropometría
3.
Ecol Food Nutr ; 63(3): 204-228, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38495022

RESUMEN

Human-wildlife interactions can affect human wellbeing and wildlife population persistence. This paper addresses the perceived impacts of wildlife on agropastoral food production in the Tarangire ecosystem of northern Tanzania. It is based on sixteen months of collaborative ethnographic fieldwork with agropastoral Maasai communities (2019-2020; 2022; 2023), 240 semi-structured interviews, and a household survey (n = 1076). People felt that caterpillars, elephants, and zebras had the most significant effects on crop production, while hyenas were responsible for the bulk of livestock depredation by carnivores. These social costs of wildlife merit further attention from conservation policy makers.


Asunto(s)
Animales Salvajes , Tanzanía , Animales , Humanos , Conservación de los Recursos Naturales , Ganado , Ecosistema , Agricultura , Masculino , Femenino , Elefantes , Equidae , Hyaenidae , Adulto , Abastecimiento de Alimentos
4.
Proc Natl Acad Sci U S A ; 117(18): 9793-9799, 2020 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-32284419

RESUMEN

The development of pastoralism transformed human diets and societies in grasslands worldwide. The long-term success of cattle herding in Africa has been sustained by dynamic food systems, consumption of a broad range of primary and secondary livestock products, and the evolution of lactase persistence (LP), which allows digestion of lactose into adulthood and enables the milk-based, high-protein, low-calorie diets characteristic of contemporary pastoralists. Despite the presence of multiple alleles associated with LP in ancient and present-day eastern African populations, the contexts for selection for LP and the long-term development of pastoralist foodways in this region remain unclear. Pastoral Neolithic (c 5000 to 1200 BP) faunas indicate that herders relied on cattle, sheep, and goats and some hunting, but direct information on milk consumption, plant use, and broader culinary patterns is rare. Combined chemical and isotopic analysis of ceramic sherds (n = 125) from Pastoral Neolithic archaeological contexts in Kenya and Tanzania, using compound-specific δ13C and Δ13C values of the major fatty acids, provides chemical evidence for milk, meat, and plant processing by ancient herding societies in eastern Africa. These data provide the earliest direct evidence for milk product consumption and reveal a history of reliance on animal products and other nutrients, likely extracted through soups or stews, and plant foods. They document a 5,000-y temporal framework for eastern Africa pastoralist cuisines and cultural contexts for selection for alleles distinctive of LP in eastern Africa.


Asunto(s)
Arqueología , Dieta , Análisis de los Alimentos/historia , Leche/química , Animales , Isótopos de Carbono/química , Bovinos , Cerámica/historia , Dieta/historia , Ácidos Grasos/química , Ácidos Grasos/aislamiento & purificación , Cabras , Historia Antigua , Migración Humana/historia , Humanos , Lactasa/química , Lactosa/química , Ganado , Carne/análisis , Ovinos
5.
J Environ Manage ; 341: 118086, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37167700

RESUMEN

Transhumance routes mark the natural path followed by herds during their seasonal movements. These routes are disappearing in many European countries. In Italy, a few fragments survive in Molise, in southern Italy, called Tratturi and run along grassy paths. The Tratturi are considered to be of archaeological, economic and landscape interest, sources of cultural and environmental attraction, protected by a national law. However, the landscapes connected to the Tratturi are disappearing both as a consequence of non-use and as a consequence of the advancement of wooded areas, and this poses a problem related to the governance system that involves many stakeholders, both at international, national and local level. The study, through the use of the combined approach of Stakeholder Basic Analysis and Social Network Analysis, identifies the role of the stakeholders involved, their power, their interest and their ability to support the decision-making system. Furthermore, the paper uses multivariate statistical analysis to detect the key stakeholders. A new model of governance, allowing to preserve the Tratturi and to enhance the services they can provide, is introduced, and it is named Authority for the Conservation and Enhancement of Tratturi (ACET). This study can help to identify appropriate management models for ancient routes based on all stakeholders involved, and more generally to implement shared and co-responsible planning choices in socio-ecological systems.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Italia , Europa (Continente)
6.
Environ Manage ; 71(1): 29-39, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-34837100

RESUMEN

Pastoralism as a mode of production has had an important bearing on the livelihoods of many people in arid and semiarid environments. In the recent decades' policies for land management in pastoral communities have changed from customary to statutory policies. This study analysed the dynamics of land management and their influence on the pastoral livelihood system at Kimana and Njoro villages in Kiteto district, northern Tanzania. Data for the study were collected from two focus groups, six key informants at the district level, and 296 households (equivalent to 10.1%) using household questionnaires, Findings show that whereas land is managed under customary and statutory laws, the emphasis is more on statutory laws. Statutory laws foster individualization of land ownership to some activities such as crop production, whereas communal lands are left for animal grazing only. Under statutory laws, individual land ownership is likely to be influenced by crop production, male-headed households, climate change, and resource use conflicts. However, statutory laws cannot guarantee sustainable resource management as the natural resources management institutions cannot dictate activities done in individual lands, as opposed to traditional systems. There is a need to harmonize traditional and modern forms of land management for increasing productivity and enhancing sustainable natural resources management.


Asunto(s)
Conservación de los Recursos Naturales , Composición Familiar , Masculino , Recursos Naturales , Encuestas y Cuestionarios , Tanzanía , Humanos
7.
BMC Biol ; 19(1): 259, 2021 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-34872534

RESUMEN

BACKGROUND: Hunter-gatherer lifestyles dominated the southern African landscape up to ~ 2000 years ago, when herding and farming groups started to arrive in the area. First, herding and livestock, likely of East African origin, appeared in southern Africa, preceding the arrival of the large-scale Bantu-speaking agro-pastoralist expansion that introduced West African-related genetic ancestry into the area. Present-day Khoekhoe-speaking Namaqua (or Nama in short) pastoralists show high proportions of East African admixture, linking the East African ancestry with Khoekhoe herders. Most other historical Khoekhoe populations have, however, disappeared over the last few centuries and their contribution to the genetic structure of present-day populations is not well understood. In our study, we analyzed genome-wide autosomal and full mitochondrial data from a population who trace their ancestry to the Khoekhoe-speaking Hessequa herders from the southern Cape region of what is now South Africa. RESULTS: We generated genome-wide data from 162 individuals and mitochondrial DNA data of a subset of 87 individuals, sampled in the Western Cape Province, South Africa, where the Hessequa population once lived. Using available comparative data from Khoe-speaking and related groups, we aligned genetic date estimates and admixture proportions to the archaeological proposed dates and routes for the arrival of the East African pastoralists in southern Africa. We identified several Afro-Asiatic-speaking pastoralist groups from Ethiopia and Tanzania who share high affinities with the East African ancestry present in southern Africa. We also found that the East African pastoralist expansion was heavily male-biased, akin to a pastoralist migration previously observed on the genetic level in ancient Europe, by which Pontic-Caspian Steppe pastoralist groups represented by the Yamnaya culture spread across the Eurasian continent during the late Neolithic/Bronze Age. CONCLUSION: We propose that pastoralism in southern Africa arrived through male-biased migration of an East African Afro-Asiatic-related group(s) who introduced new subsistence and livestock practices to local southern African hunter-gatherers. Our results add to the understanding of historical human migration and mobility in Africa, connected to the spread of food-producing and livestock practices.


Asunto(s)
Genética de Población , Migración Humana , África Austral , Población Negra/genética , ADN Mitocondrial/genética , Migración Humana/historia , Humanos , Masculino
8.
J Environ Manage ; 311: 114763, 2022 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-35279492

RESUMEN

Communities in and around protected areas are exposed to a higher level of human-wildlife interactions. The conservation practice with persistently adverse local livelihood outcomes can potentially aggravate such interactions leading to conflict. In our study, we examined how perceptions of HWC have formed in a protected area of the Trans-Himalayas whose conservation program collides with a centuries-long tradition of transhumance pastoralism. To examine determinants of depredation and how conflict perception has developed there, along with the socioeconomic and ecological interactions underlying those trends, we collected data using household surveys, key informant interviews, and focus group discussions. We employed Poisson-logit maximum-likelihood hurdle, binary logit, and multinomial ordered logit regressions in order to explore the determinants of annual livestock depredation, predator attacks on the shed, and household-level perceptions of HWC, respectively. Depredation and encounters with wildlife were the principal causes of perceived HWC, and depredation caused an average household-level loss of US $422.5, up to 23.28% of annual income in some households. Predators' attacks on high-quality sheds were relatively infrequent but more common in areas with perceived habitat degradation. Social customs, pastoral practices, and the present compensation mechanism were identified as being antithetical to conflict reduction and sustainable pastureland management. Further analysis revealed that a diversity of livelihoods, however, lowered conflict perception formation. The identified socio-ecological factors will continue to increase depredation, exacerbate perceived HWC, and degrade pastureland unless local conservation authorities take appropriate remedial measures.

9.
Environ Monit Assess ; 194(11): 833, 2022 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-36166173

RESUMEN

Quantifying the recent LULC changes and associated impacts on pastoral and agro-pastoral livelihood systems is important since the effects of LULC changes on environmental resources and human livelihood are not fully understood in our study area. This paper analysed the trend of land use/land cover (LULC) dynamics and its implications on natural resources and human livelihood in the Middle Awash Valley, Central Ethiopian Rift Valley. For the purpose, Landsat imageries of thematic mapper (1987), enhanced thematic mapper (2002) and operational land imager and thermal infrared sensor (2016) were employed and analysed using Remote Sensing and Geographic Information System (GIS) software and techniques, and qualitative data analysis had been performed as well. The results showed that cultivated land expanded at a rate of 2.6% year-1, whereas forestland and grassland shrunk at a rate of 1.2% year-1 and 2.4% year-1, respectively. The invasive Prosopis juliflora has been expanded from 3.7% in 1987 to 37.9% in 2016 at a rate of 1.2% year-1. The introduction of both small- and large-scale commercial irrigation farming and the implementation of villagization programme focused on transforming pastoralists into sedentary lifestyles. Consequently, irrigation farming, launching of villagization, climate variability as in series of droughts, construction of water dam and the rapid expansion of Prosopis juliflora were the major drivers of LULC changes in the study area. Although we found some positive developments such as improvement on infrastructural and social services (e.g. school and domestic water supply), income diversification and ecological benefits from Prosopis juliflora (e.g. saline soil treatment, carbon sequestration and soil erosion control), there were a range of negative impacts resulting from LULC changes in the study area. LULC changes reduced quality of rangeland resources as the ecologically and economically valuable indigenous tree and grass varieties were significantly degraded. As a result, the traditional pastoral livelihood system has been much vulnerable with the LULC dynamism of the study area. Furthermore, the implementation of the villagization programme has brought socioeconomic impacts on the community and challenges on the ecology, e.g. changing productive rangeland to irrigation crop farms. Our research results, thus, suggest the urgent need for relevant policy interventions in support of the pastoral livelihoods and landscapes with the modification in the implementation of villagization as well as irrigation farming programmes and its better management and controlling Prosopis juliflora expansion in the study area.


Asunto(s)
Conservación de los Recursos Naturales , Prosopis , Agricultura/métodos , Conservación de los Recursos Naturales/métodos , Monitoreo del Ambiente/métodos , Etiopía , Humanos , Suelo , Agua
10.
Proc Biol Sci ; 288(1955): 20211204, 2021 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-34284627

RESUMEN

Recently expanded estimates for when humans arrived on Madagascar (up to approximately 10 000 years ago) highlight questions about the causes of the island's relatively late megafaunal extinctions (approximately 2000-500 years ago). Introduced domesticated animals could have contributed to extinctions, but the arrival times and past diets of exotic animals are poorly known. To conduct the first explicit test of the potential for competition between introduced livestock and extinct endemic megafauna in southern and western Madagascar, we generated new radiocarbon and stable carbon and nitrogen isotope data from the bone collagen of introduced ungulates (zebu cattle, ovicaprids and bushpigs, n = 66) and endemic megafauna (pygmy hippopotamuses, giant tortoises and elephant birds, n = 68), and combined these data with existing data from endemic megafauna (n = 282, including giant lemurs). Radiocarbon dates confirm that introduced and endemic herbivores briefly overlapped chronologically in this region between 1000 and 800 calibrated years before present (cal BP). Moreover, stable isotope data suggest that goats, tortoises and hippos had broadly similar diets or exploited similar habitats. These data support the potential for both direct and indirect forms of competition between introduced and endemic herbivores. We argue that competition with introduced herbivores, mediated by opportunistic hunting by humans and exacerbated by environmental change, contributed to the late extinction of endemic megafauna on Madagascar.


Asunto(s)
Extinción Biológica , Lemur , Animales , Ecosistema , Fósiles , Madagascar , Mamíferos
11.
Ecol Appl ; 31(6): e02368, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33938594

RESUMEN

Pastoral systems are the dominant livestock production system in arid and semiarid regions of sub-Saharan Africa (SSA). They are often the only form of agriculture that can be practiced due to unfavorable climate and soil fertility levels that prevent crop cultivation. Pastoralism can have negative impacts on the environment, including land degradation, greenhouse gas emissions and other gases to the atmosphere, soil erosion, water pollution and biodiversity loss. Here, we review the current knowledge on nitrogen (N) cycling, storage, and loss pathways, with an emphasis on identification of N emission hotspots. Our review reports a large uncertainty in the amount of N lost as ammonia from excreta and manure storage, as well as N losses via nitrate and DON leaching. We also found that another major N loss pathway (18%), soil N2 emissions, has not yet been measured. In order to summarize the available information, we use a virtual pastoral farm, with characteristics and management practices obtained from a real farm, Kapiti Research Station in Kenya. For outlining N flows at this virtual farm, we used published data, data from global studies, satellite imagery and geographic information system (GIS) tools. Our results show that N inputs in pastoral systems are dominated by atmospheric N deposition (˜80%), while inputs due to biological nitrogen fixation seems to play a smaller role. A major N loss pathway is nitrogen leaching (nitrate > DON) from pastures (33%). Cattle enclosures (bomas), where animals are kept during night, represent N emissions hotspots, representing 16% of the total N losses from the system. N losses via ammonia volatilization and N2 O were four and three orders of magnitude higher from bomas than from the pasture, respectively. Based on our results, we further identify future research requirements and highlight the urgent need for experimental data collection to quantify nitrogen losses from manure in animal congregation areas. Such information is needed to improve our understanding on N cycling in pastoral systems in semiarid regions and to provide practical recommendations for managers that can help with decision-making on management strategies in pastoral systems in semiarid savannas.


Asunto(s)
Fertilizantes , Ganado , Agricultura , Animales , Bovinos , Fertilizantes/análisis , Kenia , Estiércol , Nitrógeno/análisis , Suelo
12.
Proc Natl Acad Sci U S A ; 115(36): 8942-8947, 2018 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-30127016

RESUMEN

Monumental architecture is a prime indicator of social complexity, because it requires many people to build a conspicuous structure commemorating shared beliefs. Examining monumentality in different environmental and economic settings can reveal diverse reasons for people to form larger social units and express unity through architectural display. In multiple areas of Africa, monumentality developed as mobile herders created large cemeteries and practiced other forms of commemoration. The motives for such behavior in sparsely populated, unpredictable landscapes may differ from well-studied cases of monumentality in predictable environments with sedentary populations. Here we report excavations and ground-penetrating radar surveys at the earliest and most massive monumental site in eastern Africa. Lothagam North Pillar Site was a communal cemetery near Lake Turkana (northwest Kenya) constructed 5,000 years ago by eastern Africa's earliest pastoralists. Inside a platform ringed by boulders, a 119.5-m2 mortuary cavity accommodated an estimated minimum of 580 individuals. People of diverse ages and both sexes were buried, and ornaments accompanied most individuals. There is no evidence for social stratification. The uncertainties of living on a "moving frontier" of early herding-exacerbated by dramatic environmental shifts-may have spurred people to strengthen social networks that could provide information and assistance. Lothagam North Pillar Site would have served as both an arena for interaction and a tangible reminder of shared identity.


Asunto(s)
Arqueología , Ritos Fúnebres , Historia Antigua , Humanos , Kenia
13.
Annu Rev Genomics Hum Genet ; 18: 297-319, 2017 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-28426286

RESUMEN

Lactase persistence-the ability of adults to digest the lactose in milk-varies widely in frequency across human populations. This trait represents an adaptation to the domestication of dairying animals and the subsequent consumption of their milk. Five variants are currently known to underlie this phenotype, which is monogenic in Eurasia but mostly polygenic in Africa. Despite being a textbook example of regulatory convergent evolution and gene-culture coevolution, the story of lactase persistence is far from clear: Why are lactase persistence frequencies low in Central Asian herders but high in some African hunter-gatherers? Why was lactase persistence strongly selected for even though milk processing can reduce the amount of lactose? Are there other factors, outside of an advantage of caloric intake, that contributed to the selective pressure for lactase persistence? It is time to revisit what we know and still do not know about lactase persistence in humans.


Asunto(s)
Evolución Molecular , Frecuencia de los Genes , Intestinos/enzimología , Lactasa/genética , Polimorfismo de Nucleótido Simple , Animales , Regulación de la Expresión Génica , Genética de Población , Humanos , Lactosa/metabolismo , Leche/metabolismo , Selección Genética
14.
Am J Phys Anthropol ; 173(3): 423-436, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32812238

RESUMEN

OBJECTIVES: Archeological evidence shows that first nomadic pastoralists came to the African Sahel from northeastern Sahara, where milking is reported by ~7.5 ka. A second wave of pastoralists arrived with the expansion of Arabic tribes in 7th-14th century CE. All Sahelian pastoralists depend on milk production but genetic diversity underlying their lactase persistence (LP) is poorly understood. MATERIALS AND METHODS: We investigated SNP variants associated with LP in 1,241 individuals from 29 mostly pastoralist populations in the Sahel. Then, we analyzed six SNPs in the neighboring fragment (419 kb) in the Fulani and Tuareg with the -13910*T mutation, reconstructed haplotypes, and calculated expansion age and growth rate of this variant. RESULTS: Our results reveal a geographic localization of two different LP variants in the Sahel: -13910*T west of Lake Chad (Fulani and Tuareg pastoralists) and -13915*G east of there (mostly Arabic-speaking pastoralists). We show that -13910*T has a more diversified haplotype background among the Fulani than among the Tuareg and that the age estimate for expansion of this variant among the Fulani (~8.5 ka) corresponds to introduction of cattle to the area. CONCLUSIONS: This is the first study showing that the "Eurasian" LP allele -13910*T is widespread both in northern Europe and in the Sahel; however, it is limited to pastoralists in the Sahel. Since the Fulani haplotype with -13910*T is shared with contemporary Eurasians, its origin could be in a region encompassing the Near East and northeastern Africa in a population ancestral to both Saharan pastoralists and European farmers.


Asunto(s)
Población Negra , Etnicidad , Lactasa/genética , Polimorfismo de Nucleótido Simple/genética , África del Norte , Animales , Antropología Física , Árabes/genética , Árabes/estadística & datos numéricos , Población Negra/genética , Población Negra/estadística & datos numéricos , Dieta , Etnicidad/genética , Etnicidad/estadística & datos numéricos , Haplotipos , Humanos , Leche , Migrantes , Población Blanca/genética , Población Blanca/estadística & datos numéricos
15.
Am J Phys Anthropol ; 171(1): 120-141, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31688956

RESUMEN

OBJECTIVES: This article explores the scale and seasonal patterns of mobility at the complex settlement site of Qizqala during the Middle Bronze Age (2400-1,500 BCE). By integrating human bone, teeth, and environmental samples this research tests the hypothesis of the persistent importance of community-wide seasonal pastoral transhumance during the early formation of complex settlement systems of the South Caucasus. METHODS: This research applies stable oxygen and radiogenic strontium isotope analyses on incremental samples of human tooth enamel, bulk tooth enamel, and bone to resolve mobility patterns. Sequential and bulk sampling techniques elucidate seasonal and residential mobility behaviors. Extensive environmental isotope samples of plant and water were collected through regional survey and establish local and regional isotopic baselines, which are compared to human isotope analysis results. RESULTS: Qizqala individuals exhibit low isotopic variability compared to regional contemporaries. 87 Sr/86 Sr ratios from human remains indicate seasonal and residential isotopic variability within the baseline ranges of local landscapes. δ18 O values display erratic patterns, but correspond to seasonal variability with fluctuations between highland and lowland altitudinal zone baseline values. CONCLUSIONS: Results suggest that isotopic analysis of multiple elements and sequential enamel samples offers finer resolution on the complexities of human mobility strategies and elucidate the daily lives of often overlooked mobile populations. Higher resolution of individual mobility reveals shared routine behaviors that underscore the importance of diverse social collaborations in forming complex polities in the South Caucasus.


Asunto(s)
Migración Humana/historia , Estilo de Vida/historia , Arqueología , Azerbaiyán , Huesos/química , Historia Antigua , Humanos , Isótopos de Estroncio/análisis , Diente/química
16.
Afr Archaeol Rev ; 37(3): 491-495, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32863519

RESUMEN

High-resolution paleoenvironmental research allows us to pinpoint the tempo and amplitude of past climate changes. Abrupt climate events have axiomatically triggered cascades of adjustments, in vegetation, fauna, humans, and pathogens. This essay focuses on the abrupt end of the African Humid Episode (9000-6000 cal BP), ca. 5000 cal BP in the Sahara. Neolithic pastoralists, practicing transhumance between sandy lowlands and Saharan mountains, adopted new cultural practices: cattle burials and livestock bone deposits in built installations. Their ritual nature is indisputable. But ritual for what? If considered from the perspective of livestock zoonoses, such practices may point to the "dark side" of cultural adjustments-strategies to counter human and livestock diseases. Livestock zoonoses are constant sources of emerging infectious diseases (EID) in the present, as they were in the past. Sustained research on livestock and human health are of paramount importance given the accelerating rate of world urbanization.


La haute résolution des recherches paléoenvironnementales actuelles permet de préciser la chronologie et l'amplitude précises des changements climatiques passés. Axiomatiquement, de brusques changements climatiques ont déclenché des cascades d'ajustements, de la végétation, la faune, les humains et les agents pathogènes. Cet article porte sur la fin abrupte de l'Episode Humide Africain (9000-6000 Cal yr BP), autour de 5000 calBP dans le Sahara. Les pasteurs néolithiques, transhumant entre les basses terres sablonneuses et les montagnes sahariennes, ont adopté de nouvelles pratiques culturelles: enterrements de bétail et dépôts de leurs os dans des installations construites. Leur nature rituelle est incontestable. Mais rituel pour Quoi? Si elles sont prises en considération du point de vue des zoonoses du bétail, de telles pratiques peuvent indiquer le « côté obscur ¼ des ajustements culturels, des stratégies de lutte contre les maladies humaines et du bétail. Les zoonoses sont des sources constantes de maladies infectieuses émergentes [EID] dans le présent, ainsi que dans le passé, en effet. En raison de l'urbanisation acceleree, les recherches soutenues sur la santé humaine et du bétail sont d'une importance capitale.

17.
BMC Genomics ; 20(1): 915, 2019 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-31791255

RESUMEN

BACKGROUND: Human population history in the Holocene was profoundly impacted by changes in lifestyle following the invention and adoption of food-production practices. These changes triggered significant increases in population sizes and expansions over large distances. Here we investigate the population history of the Fulani, a pastoral population extending throughout the African Sahel/Savannah belt. RESULTS: Based on genome-wide analyses we propose that ancestors of the Fulani population experienced admixture between a West African group and a group carrying both European and North African ancestries. This admixture was likely coupled with newly adopted herding practices, as it resulted in signatures of genetic adaptation in contemporary Fulani genomes, including the control element of the LCT gene enabling carriers to digest lactose throughout their lives. The lactase persistence (LP) trait in the Fulani is conferred by the presence of the allele T-13910, which is also present at high frequencies in Europe. We establish that the T-13910 LP allele in Fulani individuals analysed in this study lies on a European haplotype background thus excluding parallel convergent evolution. We furthermore directly link the T-13910 haplotype with the Lactase Persistence phenotype through a Genome Wide Association study (GWAS) and identify another genomic region in the vicinity of the SPRY2 gene associated with glycaemic measurements after lactose intake. CONCLUSIONS: Our findings suggest that Eurasian admixture and the European LP allele was introduced into the Fulani through contact with a North African population/s. We furthermore confirm the link between the lactose digestion phenotype in the Fulani to the MCM6/LCT locus by reporting the first GWAS of the lactase persistence trait. We also explored other signals of recent adaptation in the Fulani and identified additional candidates for selection to adapt to herding life-styles.


Asunto(s)
Población Negra/genética , Lactasa/genética , Europa (Continente) , Evolución Molecular , Flujo Génico , Estudio de Asociación del Genoma Completo , Humanos , Migrantes
18.
Ann Hum Genet ; 83(1): 11-22, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30264486

RESUMEN

The genetic trait of lactase persistence (LP) evolved as an adaptation to milking pastoralism in the Old World and is a well-known example of positive natural selection in humans. However, the specific mechanisms conferring this selective advantage are unknown. To understand the relationship between milk drinking, LP, growth, reproduction, and survival, communities of the Coquimbo Region in Chile, with recent adoption of milking agropastoralism, were used as a model population. DNA samples and data on stature, reproduction, and diet were collected from 451 participants. Lactose tolerance tests were done on 41 of them. The European -13,910*T (rs4988235) was the only LP causative variant found, showing strong association (99.6%) with LP phenotype. Models of associations of inferred LP status and milk consumption, with fertility, mortality, height, and weight were adjusted with measures of ancestry and relatedness to control for population structure. Although we found no statistically significant effect of LP on fertility, a significant effect (P = 0.002) was observed of LP on body mass index (BMI) in males and of BMI on fertility (P = 0.003). These results fail to support a causal relationship between LP and fertility yet suggest the idea of a nutritional advantage of LP. Furthermore, the proportion of European ancestry around the genetic region of -13,910*T is significantly higher (P = 0.008) than the proportion of European ancestry genome-wide, providing evidence of recent positive selection since European-Amerindian admixture. This signature was absent in nonpastoralist Latin American populations, supporting the hypothesis of specific adaptation to milking agropastoralism in the Coquimbo communities.


Asunto(s)
Agricultura , Etnicidad/genética , Evolución Molecular , Lactasa/genética , Animales , Índice de Masa Corporal , Chile , Femenino , Fertilidad , Frecuencia de los Genes , Estudios de Asociación Genética , Cabras , Haplotipos , Humanos , Intolerancia a la Lactosa/genética , Masculino , Leche , Fenómenos Fisiológicos de la Nutrición , Fenotipo , Polimorfismo de Nucleótido Simple
19.
Proc Biol Sci ; 286(1910): 20191273, 2019 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-31480978

RESUMEN

Mobile pastoralists are thought to have facilitated the first trans-Eurasian dispersals of domesticated plants during the Early Bronze Age (ca 2500-2300 BC). Problematically, the earliest seeds of wheat, barley and millet in Inner Asia were recovered from human mortuary contexts and do not inform on local cultivation or subsistence use, while contemporaneous evidence for the use and management of domesticated livestock in the region remains ambiguous. We analysed mitochondrial DNA and multi-stable isotopic ratios (δ13C, δ15N and δ18O) of faunal remains from key pastoralist sites in the Dzhungar Mountains of southeastern Kazakhstan. At ca 2700 BC, Near Eastern domesticated sheep and goat were present at the settlement of Dali, which were also winter foddered with the region's earliest cultivated millet spreading from its centre of domestication in northern China. In the following centuries, millet cultivation and caprine management became increasingly intertwined at the nearby site of Begash. Cattle, on the other hand, received low levels of millet fodder at the sites for millennia. By primarily examining livestock dietary intake, this study reveals that the initial transmission of millet across the mountains of Inner Asia coincided with a substantial connection between pastoralism and plant cultivation, suggesting that pastoralist livestock herding was integral for the westward dispersal of millet from farming societies in China.


Asunto(s)
Agricultura/historia , Productos Agrícolas/historia , Mijos , Animales , Arqueología , Bovinos , China , Domesticación , Cabras , Historia Antigua , Humanos , Kazajstán , Ganado , Datación Radiométrica , Ovinos
20.
Disasters ; 43 Suppl 3: S318-S344, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30945770

RESUMEN

Darfur farming and pastoralist livelihoods are both adaptations to the environmental variability that characterises the region. This article describes this adaptation and the longer-term transformation of these specialised livelihoods from the perspective of local communities. Over several decades farmers and herders have experienced a continuous stream of climate, conflict and other shocks, which, combined with wider processes of change, have transformed livelihoods and undermined livelihood institutions. Their well-rehearsed specialist strategies are now combined with new strategies to cope. These responses help people get by in the short term but risk antagonising not only their specialist strategies but also those of others. A combination of factors has undermined the former integration between farming and pastoralism and their livelihood institutions. Efforts to build resilience in similar contexts must take a long-term view of livelihood adaptation as a specialisation, and consider the implications of new strategies for the continuity and integration of livelihood specialisations.


Asunto(s)
Agricultura , Planificación en Desastres/organización & administración , Resiliencia Psicológica , Cambio Climático , Conflicto Psicológico , Humanos , Sudán
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